The improvement of outcome in patients with ovarian cancer by an anti-angiogenic therapy has been shown in large clinical trials. However, the only option currently available is the anti-VEGF-A antibody, which efficacy is limited. Therefore, we aim to develop a new anti-angiogenic drug for ovarian cancer. As NF-κB signaling has the potential to regulate several angiogenic factors including VEGF-A, we determined to identify the significance of NF-κB activation in ovarian cancer and to investigate the possibility of a novel NF-κB inhibitor as an anti-angiogenic drug. Immunohistochemical analyses using ovarian cancer tissues showed that NF-κB activation is an independent prognostic factor. A specific NF-κB inhibitor led to the inhibition of angiogenesis in vitro and in vivo. In a xenograft model, the treatment of NF-κB inhibitor significantly suppressed peritoneal dissemination. Anti-angiogenic therapy targeting NF-κB signaling is a potential future option to treat ovarian cancer.